Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeox...Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeoxynucleotide (AS PS-ODN) was synthesized and puri?ed. Telomerase activity was detected by Telomerase PCR ELASA kit and cell apoptosis was observed by morphological method and determined by ?owcytometry. Results: AS PS-ODN could signi?cantly inhibit telomerase activity by down regulat- ing the hTERT expression, and increase the susceptibility of leukemic cells to CDDP-induced apoptosis. Conclusion: Inhibition of telomerase with hTERT antisense can increases the susceptibility of leukemic cells to CDDP-induced apoptosis.展开更多
Bone marrow microenvironment (BMM) is the main sanctuary of leukemic stem cells (LSCs) and protects these cells against conventional therapies. However, it may open up an opportunity to target LSCs by breaking the clo...Bone marrow microenvironment (BMM) is the main sanctuary of leukemic stem cells (LSCs) and protects these cells against conventional therapies. However, it may open up an opportunity to target LSCs by breaking the close connection between LSCs and the BMM. The elimination of LSCs is of high importance, since they follow cancer stem cell theory as a part of this population. Based on cancer stem cell theory, a cell with stem cell-like features stands at the apex of the hierarchy and produces a heterogeneous population and governs the disease. Secretion of cytokines, chemokines, and extracellular vesicles, whether through autocrine or paracrine mechanisms by activation of downstream signaling pathways in LSCs, favors their persistence and makes the BMM less hospitable for normal stem cells. While all details about the interactions of the BMM and LSCs remain to be elucidated, some clinical trials have been designed to limit these reciprocal interactions to cure leukemia more effectively. In this review, we focus on chronic myeloid leukemia and acute myeloid leukemia LSCs and their milieu in the bone marrow, how to segregate them from the normal compartment, and finally the possible ways to eliminate these cells.展开更多
AIM To evaluate the importance of the CD34+CD38-cell population when compared to the CD34+CD38+/low and CD34+CD38+/high leukemic cell sub-populations and to determine its correlations with leukemia characteristics and...AIM To evaluate the importance of the CD34+CD38-cell population when compared to the CD34+CD38+/low and CD34+CD38+/high leukemic cell sub-populations and to determine its correlations with leukemia characteristics and known prognostic factors, as well as with response to therapy and survival.METHODS Two hundred bone marrow samples were obtained at diagnosis from 200 consecutive patients with newly diagnosed acute myeloid leukemia(AML) were studied between September 2008 and December 2010 at our Institution(Hematology Department, Lyon, France). The CD34/CD38 cell profile was analyzed by multiparameter flowcytometry approach using 8 C panels and FACS CANTO and Diva software(BD Bioscience).RESULTS We analyzed CD34 and CD38 expression in bone marrow samples of 200 AML patients at diagnosis, and investigated the prognostic value of the most immature CD34+CD38-population. Using a cut-off value of 1% of CD34+CD38-from total "bulk leukemic cells" we found that a high(> 1%) level of CD34+CD38-blasts at diagnosis was correlated with advanced age, adverse cytogenetics as well as with a lower rate of complete response after induction and shorter disease-free survival. In a multivariate analysis considering age, leukocytosis, the % of CD34+ blasts cells and the standardized cytogenetic and molecular risk subgroups, a percentage of CD34+CD38-leukemic cells > 1% was an independent predictor of DFS [HR = 2.8(1.02-7.73), P = 0.04] and OS [HR = 2.65(1.09-6.43), P = 0.03].CONCLUSION Taken together, these results show that a CD34/CD38 "backbone" for leukemic cell analysis by multicolour flowcytometry at diagnosis provides useful prognostic information.展开更多
Spurred by better understanding of disease biology,improvements in molecular diagnostics,and the development of targeted therapies,the treatment of acute myeloid leukemia(AML)has undergone significant evolution in rec...Spurred by better understanding of disease biology,improvements in molecular diagnostics,and the development of targeted therapies,the treatment of acute myeloid leukemia(AML)has undergone significant evolution in recent years.Arguably,the most exciting shift has come from the success of treatment with the B-cell lymphoma-2 inhibitor venetoclax.When given in combination with a hypomethylating agent or low dose cytarabine,venetoclax demonstrates high response rates,some of which are durable.In spite of this,relapses after venetoclax treatment are common,and much interest exists in elucidating the mechanisms of resistance to the drug.Alterations in leukemic stem cell metabolism have been identified as a possible escape route,and clinical trials focusing on targeting metabolism in AML are ongoing.This review article highlights current research regarding venetoclax treatment and resistance in AML with a focus on cellular metabolism.展开更多
The Polycomb group protein Bmi1 is a constituent of the Polycomb repressive complex 1, and it is an important molecule for the regulation of the self-renewal of hematopoietic stem cells. In the field of clinical hemat...The Polycomb group protein Bmi1 is a constituent of the Polycomb repressive complex 1, and it is an important molecule for the regulation of the self-renewal of hematopoietic stem cells. In the field of clinical hematology, there are reports that the level of Bmi1 expression in blast cells is related to the prognosis of acute myeloid leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. We investigated whether the level of Bmi1 expression in leukemic cells is related to the prognosis and the characteristics of childhood acute lymphoblastic leukemia. In all the leukemic blast cells, Bmi1 gene expression was lower value than that in normal B cells. There were no correlations between the level of Bmi1 gene expression in leukemic blast cells and other parameters, including prognosis. Here, we report that the level of Bmi1 expression in blast cells is not related to the prognosis of pediatric acute lymphoblastic leukemia.展开更多
ABC immunoperoxidase was used to test the effects of rhTGF-β1 and rhGM-CSF on receptor expressions in J6-1 and J6-2 leukemic cell lines. Computer assisted image analysis system was introduced to evaluate positive ind...ABC immunoperoxidase was used to test the effects of rhTGF-β1 and rhGM-CSF on receptor expressions in J6-1 and J6-2 leukemic cell lines. Computer assisted image analysis system was introduced to evaluate positive index of time-and dose-dependent specimens. The expression of c-kit was elevated both in positive rate and positive index by TGF-01 in both time- and dose-dependent manners. Ing/ml rhTGF-β1 simultaneously enhanced the expression of c-fms and PDGF-R which is not detected in 50 ng / ml GM-CSF treatment. Endoglin was down-regulated after TGF-β treatment and up-regulated in J6-2 cells after GM-CSF treatment, c-kit Expression was elevated by TGF-β in J6-1 cells while decreased by both in J6-2 cells.展开更多
In order to investigate the expression and functional role of HERG1 K+ channels in leukemic cells and leukemic stem cells (LSCs), RT-PCR was used to detect the HERG1 K+ channels expression in leukemic cells and LSCs. ...In order to investigate the expression and functional role of HERG1 K+ channels in leukemic cells and leukemic stem cells (LSCs), RT-PCR was used to detect the HERG1 K+ channels expression in leukemic cells and LSCs. The functional role of HERG1 K+ channels in leukemic cell proliferation was measured by MTT assay, and cell cycle and apoptosis were analyzed by flow cy- tometry. The results showed that herg mRNA was expressed in CD34+/CD38-, CD123+ LSCs but not in circulating CD34+ cells. Herg mRNA was also up-regulated in leukemia cell lines K562 and HL60 as well as almost all the primary leukemic cells while not in normal peripheral blood mononuclear cells (PBMNCs) and the expression of herg mRNA was not associated with the clinical and cytoge- netic features of leukemia. In addition, leukemic cell proliferation was dramatically inhibited by HERG K+ channel special inhibitor E-4031. Moreover, E-4031 suppressed the cell growth by induc- ing a specific block at the G1/S transition phase of the cell cycle but had no effect on apoptosis in leukemic cells. The results suggested that HERG1 K+ channels could regulate leukemic cells prolif- eration and were necessary for leukemic cells to proceed with the cell cycle. HERG1 K+ channels may also have oncogenic potential and may be a biomarker for diagnosis of leukemia and a novel potential pharmacological target for leukemia therapy.展开更多
Objective: To explore the effects of IL-10 on acute leukemic immune evasion.Methods: Plasma concentrations of IL-10 were measured by ELISA in 56 first-visit acute leukemic patients.And expressions of IL-10 on leukemic...Objective: To explore the effects of IL-10 on acute leukemic immune evasion.Methods: Plasma concentrations of IL-10 were measured by ELISA in 56 first-visit acute leukemic patients.And expressions of IL-10 on leukemic cells in 30 patients were measured by indirect immunofluorescence technique. Results:Compared with those in control group,IL-10 concentrations increased significantly in first-visit acute leukemic patients.And there was a slight but not significant decrease of IL-10 in patients with acute lymphocytic leukemia(ALL) compared with those with acute non lymphocytic leukemic(ANLL).After intensive chemotherapy,there was a significant decrease of IL-10 in completely remitted(CR) patients,especially in those with ANLL,but there was still a significant increase compared with those in control group.The positive rate of cells giving out yellow-green bright fluorescence on membranes was 10%-80%;there were 18 patients expressing IL-10(18/30,60%) positively:among them 11 with ANLL(11/19,58%) and 7 with ALL(7/11,64%) respectively while that of peripheral mononucleate cells in control group was 13%.Compared with that in control group,there was a significant increase of positive rate in ANLL and ALL but with no significant difference between ANLL and ALL.Conclusion: Probably as one of important mechanisms of acute leukemic immune evasion,IL-10 secreted by leukemic cells,contributing to the immunosuppressive state at the tumor site,increase significantly in acute leukemic patients.展开更多
Objective: To explore the expressions of IL-10 on leukemic cells in acute leukemia patients and its significance. Methods: The expressions of IL-10 on leukemic cells in thirty patients was measured by indirect immunof...Objective: To explore the expressions of IL-10 on leukemic cells in acute leukemia patients and its significance. Methods: The expressions of IL-10 on leukemic cells in thirty patients was measured by indirect immunofluorescence technique. Results: Observed yellow-green bright fluorescence on leukemic cells membrane, the positive rate of cells was 10-80%, there were 18 patients expressing IL-10 (18/30, 60%) positively, among them 11 with ANLL (11/19, 58%) and 7 with ALL (7/11, 64%) respectively while that of peripheral mononucleate cells in control group was 13%. Compared with that in the control group, there was a significant increase of positive rate in ANLL and ALL but with no significant difference between ANLL and ALL. Conclusion: IL-10 secreted by leukemic cells, contributed to the immunosuppressive state at the tumor site. This is probably one of the important mechanisms of acute leukemic escape.展开更多
BACKGROUND Accumulating evidence demonstrates that autoimmune hematopoietic failure and myeloid neoplasms have an intrinsic relationship with regard to clonal hematopoiesis and disease evolution.In approximately 10%-1...BACKGROUND Accumulating evidence demonstrates that autoimmune hematopoietic failure and myeloid neoplasms have an intrinsic relationship with regard to clonal hematopoiesis and disease evolution.In approximately 10%-15%of patients with severe aplastic anemia(SAA),the disease phenotype is transformed into myeloid neoplasms following antithymocyte globulin plus cyclosporine-based immunosuppressive therapy.In some of these patients,myeloid neoplasms appear during or shortly after immunosuppressive therapy.Leukemic transformation in SAA patients during anti-tuberculosis treatment has not been reported.CASE SUMMARY A middle-aged Chinese female had a 6-year history of non-SAA and a 2-year history of paroxysmal nocturnal hemoglobinuria(PNH).With aggravation of systemic inflammatory symptoms,severe pancytopenia developed,and her hemoglobinuria disappeared.Laboratory findings in cytological,immunological and cytogenetic analyses of bone marrow samples met the diagnostic criteria for“SAA.”Definitive diagnosis of disseminated tuberculosis was made in the search for infectious niches.Remarkable improvement in hematological parameters was achieved within 1 mo of anti-tuberculosis treatment,and complete hematological remission was achieved within 4 mo of treatment.Frustratingly,the hematological response lasted for only 3 mo,and pancytopenia reemerged.At this time,cytological findings(increased bone marrow cellularity and an increased percentage of myeloblasts that accounted for 16.0%of all nucleated hematopoietic cells),immunological findings(increased percentage of cluster of differentiation 34+cells that accounted for 12.28%of all nucleated hematopoietic cells)and molecular biological findings(identification of somatic mutations in nucleophosmin-1 and casitas B-lineage lymphoma genes)revealed that“SAA”had transformed into acute myeloid leukemia with mutated nucleophosmin-1.The transformation process suggested that the leukemic clones were preexistent but were suppressed in the PNH and SAA stages,as development of symptomatic myeloid neoplasm through acquisition and accumulation of novel oncogenic mutations is unlikely in an interval of only 7 mo.Aggravation of inflammatory stressors due to disseminated tuberculosis likely contributed to the repression of normal and leukemic hematopoiesis,and the relief of inflammatory stressors due to anti-tuberculosis treatment contributed to penetration of neoplastic hematopoiesis.The concealed leukemic clones in the SAA and PNH stages raise the possibility of an inflammatory stress-fueled antileukemic mechanism.CONCLUSION Aggravated inflammatory stressors can repress normal and leukemic hematopoiesis,and relieved inflammatory stressors can facilitate penetration of neoplastic hematopoiesis.展开更多
Sunitinib is an orally administered, multi-target tyrosine kinase inhibitor that has been approved by the FDA for the treatment of renal cell carcinoma and imatinib resistant gastro-intestinal tumors. Anti-leukemic ac...Sunitinib is an orally administered, multi-target tyrosine kinase inhibitor that has been approved by the FDA for the treatment of renal cell carcinoma and imatinib resistant gastro-intestinal tumors. Anti-leukemic activity of sunitinib has been examined in early clinical trials with limited success. However, recent trials on acute myeloid leukemia (AML) patients carrying FLT3 mutations have shown promising results. Effects of sunitinib on leukemic clonogenic cells and potential leukemic stem cells have not been examined so far. We analyzed the anti-proliferative and apoptotic properties of sunitinib on AML-derived cell lines. We also tested the effect of sunitinib on AML patient derived clonogenic cells (AML-CFC), as well as flow-sorted potential leukemic progenitors. Peripheral blood or bone marrow samples were obtained from newly diagnosed AML patients and flow sorted for CD34+ CD133+ or ALDH+ cells. Umbilical cord blood derived CD34+ cells were used as normal controls. Sunitinib induced growth arrest and apoptosis in AML derived cell lines. In addition, 7 μM sunitinib induced 75% reduction of AML-CFC as compared to DMSO treated control (±6.79%;n = 4). In contrast, 7 μM sunitinib treatment of umbilical cord blood derived normal CD34+ cells showed 29% reduction in AML-CFC (±6.77%;n = 5). Treatment of ALDH+ cells sorted from 2 AML cases and CD34+ CD133+ cells from one patient showed reduction of AML-CFC on treatment with sunitinib. Our study highlighted a potent anti-proliferative and proapoptotic effect of sunitinib on AML cell lines, AML patient derived clonogenic cells and potential leukemic stem cells.展开更多
This report characterizes the J6-1 cell line derived from a Chinese acute myelomonocytic leukemia patient and previously reported to be associated with EBV. These studies showed that J6-1 cells were also infected with...This report characterizes the J6-1 cell line derived from a Chinese acute myelomonocytic leukemia patient and previously reported to be associated with EBV. These studies showed that J6-1 cells were also infected with HHV-6 as demonstrate at the DNA level by PCR and Southern blot hybridization and by expression of HHV-6 early membrane antigen on the J6-1 cell surface. Further characterization showed J6-1 was co-infected with EBV type 2. Generally, cells infected with EBV type 2 do not grow well in vitro. However, J6-1 , although difficult to maintain in vitro, has been grown for 15 years. Possibly, co-infection with HHV6 confers this property. In this regard, J6-1 cells exhibited density dependent growth which could be inhibited with an anti-HHV-6-MA monoclonal antibody(MAb). In contrast, anti-HHV-6-VCA MAb stimulated the J6-1 cell proliferation. Electron microscopic analysis showed that, morphologically, there were two types of J6-1 cell, one with lymphoblastoid features and one with a monocytoid appearance. Accordingly, the flow profile of the J6-1 cell line showed heterogeneity. with two populations comprised of CD15-, CD19+ cells with low light scatter(small cells) and a population with greater light scatter(larger cells) which was CD15+ , CD19+. The population was negative for progenitor cell markers(CD33, 34 ), and T cell markers. Southern analysis showed no T cell receptor rearrangement, however there was a clonal JH and kappa light chain expressing population. Glycocytochemical analysis showed several endogenous lectin receptors on the J6-1 cell surface: BSA-Xylose, BSA-Rhamnose, BSAGal. BSA-Lac. This cell line shares many characteristics with other monocytic/ lymphoblastoid cell lines isolated elsewhere and provides circumstantial evidence linking Herpes viruses, as least as co- factors,to leukemia cell growth.展开更多
Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymera...Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymerase chain reaction enzyme-linked immunoassay (PCR-ELISA) in K562 cellstreated with ASODN and hTERT mRNA expression was detected by reverse transcriptase polymerase chain reaction (RT-PCR).Results The hTERT mRNA level was decreased, and teloraerase activity was significantly inhibited when the K562 cells were treated withASODN for 48 h.Conclusion It is suggested that hTERT ASODN might specifically inhibit telomerase activity of K562 cells at translation level, and it isfurther proved that hTERT gene has significant correlation with telomerase activity.展开更多
To investigate whether the Bcl- 2 gene family is involved in m odulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL - 6 0 cell line and primary acute m y...To investigate whether the Bcl- 2 gene family is involved in m odulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL - 6 0 cell line and primary acute m yelogenous leukem ic cells,the Bcl- 2 family member Mcl- 1,Bax and Bak and cell cycle proteins including P2 7kipl,P2 1wafl,cyclin D3and p Rbp- were selected and their ex- pression detected by SABC imm uno- histochem ical stain m ethod.The attitude of sub- G1 peak in DNA histogram was determined by FCM.The TU NEL positive cell percentage was identified by term inal deoxynucleotidyl transferase (Td T ) - m ediated Biotin d U NP end labeling technique.It was found that when HL - 6 0 cells were treated with 2 5μm ol/ L curcumin for 2 4 h,the expression level of Mcl- 1was down- regulated,but that of Bax and Bak up- regulated time- dependently.There was significant difference in the expression level of Mcl- 1,Bax and Bak between the curcumin- treated groups and control group(P<0 .0 5 - 0 .0 1) .At the sam e time,curcumin had no effect on progress of cell cycle in prim aty acute m yelogenous leukemia at newly diagnosis,but could in- crease the peak of Sub- G1 (P<0 .0 5 ) ,and down- regulate the expression of Mcl- 1and up- regulate the expression of Bax and Bak with the difference being statistically significant.The expression of P2 7kipl,P2 1wafl and p Rbp- were elevated and thatof cyclin D3decreased in the presence of curcum in. These findings suggested thatthe Bcl- 2 gene fam ily indeed participated in the regulatory process of apoptosis induced by curcumin in HL - 6 0 cells and AML cells.Curcumin can induce apoptosis of primary acute myelogenous leukemic cells and disturb cell cycle progression of HL - 6 0 cells.The m echanism appeared to be m ediated by perturbing G0 / G1 phases checkpoints which associated with up- regulation of P2 7kipl,P2 1wafl and p Rbp- expression,and down- regulation of cyclin D3.展开更多
To investigate the inducement of cytotoxic T lym phocytes(CTL s) by antigen peptides m ixture from different leukemia cells and the cross- reaction of the m ixtures from different cell lines,antigen peptides m ixtur...To investigate the inducement of cytotoxic T lym phocytes(CTL s) by antigen peptides m ixture from different leukemia cells and the cross- reaction of the m ixtures from different cell lines,antigen peptides m ixtures were prepared from different leukemia cell lines respectively and then bound with Hsp70 in vitro.Activation and proliferation of PBMC were observed after stim u- lation with different Hsp70 - peptide complexes.The ratio of CD8+ in proliferative cells was ana- lyzed by flow cytometry.The cytotoxicity of the activated PBMC to different target cells was as- sayed.The results showed that the antigen peptides from different leukemia cell lines,bound with Hsp70 ,could activate PBMC effectively,and stimulate the activated PBMC to proliferate.The proliferative PBMC had specific cytotoxicity to corresponding leukem ia cells.CD8+ cells,account- ing for a high proportion in proliferative cells,had a specific cytotoxicity to leukemia cells from which antigen peptides were prepared,suggesting that these CD8+ cells were CTL s specific to leukemia cells.CTL s activated by Hut78- peptides or Molt4 - peptides had a significantly stronger cytotoxicity to Hut78cells,Molt4 cells and Jurkat cells than that of CTL s activated by HL - 6 0 - peptides(P<0 .0 5 ) .And the cytotoxicity of CTL s activated by Hut78/ Molt4 - peptides to Jurkat cells was significantly stronger than that of CTL s activated by either Hut78- peptides or Molt4 - peptides alone(P<0 .0 5 ) .It is concluded that antigen peptides m ixtures from leukem ia cells can induce specific antitumor CTL s.There exists cross- reactivity among antigen peptides m ixtures from different cell lines of the sam e type leukemia and more cross- reactive antigen peptides could be obtained from m ore cell lines,suggesting that antigen peptides m ixture with broad antigenic spectrum could be prepared by using multiple leukemia cell lines.展开更多
Objective: To study the molecular mechanism ofdifferent tumorigenicity in nude mice of human leukemiacell lines K562-n and K562. Methods: To analyze the genes differently expressed between K562 and K562-n cells byusin...Objective: To study the molecular mechanism ofdifferent tumorigenicity in nude mice of human leukemiacell lines K562-n and K562. Methods: To analyze the genes differently expressed between K562 and K562-n cells byusing cDNA microarray technique. Results: Among the12800 genes detected, some genes involved in materialmetabolism and material transport were differentlyexpressed between K562-n and K562 cells. These genesinclude homo sapiens placenta-specific ATP-binding cassette transporter gene, dihydrodiol dehydrogenase gene, hepatic dihydrodiol dehydrogenase gene, NAD-dependent methylene tetrahydrofolate dehydrogenase cyclohydrolase,lysophosphatidic acid acyltransferase, alpha gene,argininosuccinate lyase gene, mitochondrial isocitrtatedehydrogenase, adhesion protein SQM1 gene, dimethylarginine dimethylamino-hydrolase gene, M1subunit of ribonucleotide reductase and farnesylpyrophosphate synthetase gene. Conclusion: The hightumorigenicity of K562-n cells is related to the differentexpression of some genes concerned with cell metabolismand material transpoert.展开更多
The effect of 1,25-dihydroxyvitamin D<sub>3</sub> [1,25（OH）<sub>2</sub>D<sub>3</sub>] and13-cis-retinoic acid（RA）on the proliferation of a novel human megakaryoblasticleukemia c...The effect of 1,25-dihydroxyvitamin D<sub>3</sub> [1,25（OH）<sub>2</sub>D<sub>3</sub>] and13-cis-retinoic acid（RA）on the proliferation of a novel human megakaryoblasticleukemia cell line（HIMeg）was investigated.At the concentration of 10<sup>9</sup> 10<sup>6</sup>mol/L,1,25（OH）<sub>2</sub>D<sub>3</sub> and RA showed significant inhibition of the proliferation of themegakaryoblastic leukemic cells,which was demonstrated by the count of survival cells,incorporation of<sup>3</sup>H-TdR and<sup>3</sup>H-UR,and cloning efficiency in dose-dependent and time-dependent manners.The results can further explain the mechanism of differentiation-inducing agents and the effect of 1 ,25（OH）<sub>2</sub>D<sub>3</sub> on myelofibrosis.It is possible for1,25（OH）<sub>2</sub>D<sub>3</sub> and RA to be used to treat malignant megakaryocytic diseases.展开更多
Objective: To establish a HPLC method using fluorometric detection for quantitatively determinating intracellular accumulation of verapamil (VER). Methods: Chromatography column was packed with spherisorb ODS(250&...Objective: To establish a HPLC method using fluorometric detection for quantitatively determinating intracellular accumulation of verapamil (VER). Methods: Chromatography column was packed with spherisorb ODS(250×4.6 mm,10 μm).The mobile phase consisted of the mixture of methanol:NaAC (0.01 mol/L): diethylamine (65:35:0.25). The detect wavelength was 280/310 nm (Ex/Em). Results: The standard curve showed a good correlation between concentration and peak area within the range of 5-50 ng/ml. RSD was 0.86%, and recovery radio of loading sample, 100%. The detection limit for cell sample was 0.2-148 ng/ml. Intracellular accumulation of VER was observed to decrease from a 13 fold to 5 fold in K562/ADM cells, and from a 3.5 fold to 4.3 fold in K562/VER cells and from a 2.1 fold to 6.5 fold in K562/ADM/VER cells, compared with the relevant control cells. Conclusion: HPLC method was proved to be sensitive and specific for using to quantitatively determine the intracellular accumulation of VER.展开更多
To assess the value of CD34 + cells transferred exogenous Fas ligand (FasL) in inducing apoptosis of human leukemic cells, the CD34 + cells transfected with F asL or without, pretreated with mitomycin C, was mixed ...To assess the value of CD34 + cells transferred exogenous Fas ligand (FasL) in inducing apoptosis of human leukemic cells, the CD34 + cells transfected with F asL or without, pretreated with mitomycin C, was mixed with leukemic cell line U937 cells in presence or absence of daunorubicin (DNR) or cytosine arabinoside (Ara C). After l8 h, apoptosis of cells was detected by FCM and TUNEL. Induced for l8 h by CD34 + cells transfected with FasL or without, the ratio of apoptos is of U937 cells was (5.0±1.3) %, (10.8±0.6) % ( P < 0.01), respectively. Induced by FasL +CD34 ++DNR, FasL +CD34 ++Ara C, the ratio was (13.4±1.0) % ( P < 0.05), (17.9±1.3)% ( P <0.01), respectively. The result demonstrated that CD34 + cells transfected with exogenous FasL could induce apoptosis of human leukemic cells and showed a cytotoxic synergistic effect when used in combination with chemotherapeutic drugs, suggesting that it was possible to develop a new method in treatment of leukemia.展开更多
Leukemia is a most prevalent type of cancer around the globe. Due to major side effects of Chemotherapy and radiotherapy, scientists worked to explore the alternative source to treat leukemia. An alternative source fo...Leukemia is a most prevalent type of cancer around the globe. Due to major side effects of Chemotherapy and radiotherapy, scientists worked to explore the alternative source to treat leukemia. An alternative source for the treatment of leukemia existed in the form of curcumin, a natural phenolic compound extracted from curcuma longa plant. It exhibited anticancer properties reducing the tumor load via apoptosis and cell cycle arrested in various cancer cell lines and controlled tumor proliferation by blocking tumor inducing gene such as FLT3, Akt gene, ROS and NF-κB inhibition. At molecular level, curcumin plays a key therapeutic role in protection of normal cells by up regulation of NRF-2 that induces production of cellular antioxidants. It regulates various signaling pathways including NF-KB, JAK/STAT, PI3K/AKT and JNK pathways, thereby affecting cancer initiation, progression, and metastasis. This review described the potential of curcumin for treatment of leukemia;it affects different signaling cascades and their regulation. This study provides a preclinical foundation for future usage of curcumin in the treatment of cancer.展开更多
基金This project was supported by grants from Foundation of Science and Technology of Guangzhou city (2001-Z-037-01) and Guangdong Province (021195).
文摘Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeoxynucleotide (AS PS-ODN) was synthesized and puri?ed. Telomerase activity was detected by Telomerase PCR ELASA kit and cell apoptosis was observed by morphological method and determined by ?owcytometry. Results: AS PS-ODN could signi?cantly inhibit telomerase activity by down regulat- ing the hTERT expression, and increase the susceptibility of leukemic cells to CDDP-induced apoptosis. Conclusion: Inhibition of telomerase with hTERT antisense can increases the susceptibility of leukemic cells to CDDP-induced apoptosis.
文摘Bone marrow microenvironment (BMM) is the main sanctuary of leukemic stem cells (LSCs) and protects these cells against conventional therapies. However, it may open up an opportunity to target LSCs by breaking the close connection between LSCs and the BMM. The elimination of LSCs is of high importance, since they follow cancer stem cell theory as a part of this population. Based on cancer stem cell theory, a cell with stem cell-like features stands at the apex of the hierarchy and produces a heterogeneous population and governs the disease. Secretion of cytokines, chemokines, and extracellular vesicles, whether through autocrine or paracrine mechanisms by activation of downstream signaling pathways in LSCs, favors their persistence and makes the BMM less hospitable for normal stem cells. While all details about the interactions of the BMM and LSCs remain to be elucidated, some clinical trials have been designed to limit these reciprocal interactions to cure leukemia more effectively. In this review, we focus on chronic myeloid leukemia and acute myeloid leukemia LSCs and their milieu in the bone marrow, how to segregate them from the normal compartment, and finally the possible ways to eliminate these cells.
文摘AIM To evaluate the importance of the CD34+CD38-cell population when compared to the CD34+CD38+/low and CD34+CD38+/high leukemic cell sub-populations and to determine its correlations with leukemia characteristics and known prognostic factors, as well as with response to therapy and survival.METHODS Two hundred bone marrow samples were obtained at diagnosis from 200 consecutive patients with newly diagnosed acute myeloid leukemia(AML) were studied between September 2008 and December 2010 at our Institution(Hematology Department, Lyon, France). The CD34/CD38 cell profile was analyzed by multiparameter flowcytometry approach using 8 C panels and FACS CANTO and Diva software(BD Bioscience).RESULTS We analyzed CD34 and CD38 expression in bone marrow samples of 200 AML patients at diagnosis, and investigated the prognostic value of the most immature CD34+CD38-population. Using a cut-off value of 1% of CD34+CD38-from total "bulk leukemic cells" we found that a high(> 1%) level of CD34+CD38-blasts at diagnosis was correlated with advanced age, adverse cytogenetics as well as with a lower rate of complete response after induction and shorter disease-free survival. In a multivariate analysis considering age, leukocytosis, the % of CD34+ blasts cells and the standardized cytogenetic and molecular risk subgroups, a percentage of CD34+CD38-leukemic cells > 1% was an independent predictor of DFS [HR = 2.8(1.02-7.73), P = 0.04] and OS [HR = 2.65(1.09-6.43), P = 0.03].CONCLUSION Taken together, these results show that a CD34/CD38 "backbone" for leukemic cell analysis by multicolour flowcytometry at diagnosis provides useful prognostic information.
文摘Spurred by better understanding of disease biology,improvements in molecular diagnostics,and the development of targeted therapies,the treatment of acute myeloid leukemia(AML)has undergone significant evolution in recent years.Arguably,the most exciting shift has come from the success of treatment with the B-cell lymphoma-2 inhibitor venetoclax.When given in combination with a hypomethylating agent or low dose cytarabine,venetoclax demonstrates high response rates,some of which are durable.In spite of this,relapses after venetoclax treatment are common,and much interest exists in elucidating the mechanisms of resistance to the drug.Alterations in leukemic stem cell metabolism have been identified as a possible escape route,and clinical trials focusing on targeting metabolism in AML are ongoing.This review article highlights current research regarding venetoclax treatment and resistance in AML with a focus on cellular metabolism.
文摘The Polycomb group protein Bmi1 is a constituent of the Polycomb repressive complex 1, and it is an important molecule for the regulation of the self-renewal of hematopoietic stem cells. In the field of clinical hematology, there are reports that the level of Bmi1 expression in blast cells is related to the prognosis of acute myeloid leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. We investigated whether the level of Bmi1 expression in leukemic cells is related to the prognosis and the characteristics of childhood acute lymphoblastic leukemia. In all the leukemic blast cells, Bmi1 gene expression was lower value than that in normal B cells. There were no correlations between the level of Bmi1 gene expression in leukemic blast cells and other parameters, including prognosis. Here, we report that the level of Bmi1 expression in blast cells is not related to the prognosis of pediatric acute lymphoblastic leukemia.
基金Supported by National Natural Sciences Foundation. The abstract of this work was published in Exp Hematol (1994:22:743)
文摘ABC immunoperoxidase was used to test the effects of rhTGF-β1 and rhGM-CSF on receptor expressions in J6-1 and J6-2 leukemic cell lines. Computer assisted image analysis system was introduced to evaluate positive index of time-and dose-dependent specimens. The expression of c-kit was elevated both in positive rate and positive index by TGF-01 in both time- and dose-dependent manners. Ing/ml rhTGF-β1 simultaneously enhanced the expression of c-fms and PDGF-R which is not detected in 50 ng / ml GM-CSF treatment. Endoglin was down-regulated after TGF-β treatment and up-regulated in J6-2 cells after GM-CSF treatment, c-kit Expression was elevated by TGF-β in J6-1 cells while decreased by both in J6-2 cells.
基金a grant from National Science Foundation for Distinguished Young Scholars of China (No. 30225038)
文摘In order to investigate the expression and functional role of HERG1 K+ channels in leukemic cells and leukemic stem cells (LSCs), RT-PCR was used to detect the HERG1 K+ channels expression in leukemic cells and LSCs. The functional role of HERG1 K+ channels in leukemic cell proliferation was measured by MTT assay, and cell cycle and apoptosis were analyzed by flow cy- tometry. The results showed that herg mRNA was expressed in CD34+/CD38-, CD123+ LSCs but not in circulating CD34+ cells. Herg mRNA was also up-regulated in leukemia cell lines K562 and HL60 as well as almost all the primary leukemic cells while not in normal peripheral blood mononuclear cells (PBMNCs) and the expression of herg mRNA was not associated with the clinical and cytoge- netic features of leukemia. In addition, leukemic cell proliferation was dramatically inhibited by HERG K+ channel special inhibitor E-4031. Moreover, E-4031 suppressed the cell growth by induc- ing a specific block at the G1/S transition phase of the cell cycle but had no effect on apoptosis in leukemic cells. The results suggested that HERG1 K+ channels could regulate leukemic cells prolif- eration and were necessary for leukemic cells to proceed with the cell cycle. HERG1 K+ channels may also have oncogenic potential and may be a biomarker for diagnosis of leukemia and a novel potential pharmacological target for leukemia therapy.
文摘Objective: To explore the effects of IL-10 on acute leukemic immune evasion.Methods: Plasma concentrations of IL-10 were measured by ELISA in 56 first-visit acute leukemic patients.And expressions of IL-10 on leukemic cells in 30 patients were measured by indirect immunofluorescence technique. Results:Compared with those in control group,IL-10 concentrations increased significantly in first-visit acute leukemic patients.And there was a slight but not significant decrease of IL-10 in patients with acute lymphocytic leukemia(ALL) compared with those with acute non lymphocytic leukemic(ANLL).After intensive chemotherapy,there was a significant decrease of IL-10 in completely remitted(CR) patients,especially in those with ANLL,but there was still a significant increase compared with those in control group.The positive rate of cells giving out yellow-green bright fluorescence on membranes was 10%-80%;there were 18 patients expressing IL-10(18/30,60%) positively:among them 11 with ANLL(11/19,58%) and 7 with ALL(7/11,64%) respectively while that of peripheral mononucleate cells in control group was 13%.Compared with that in control group,there was a significant increase of positive rate in ANLL and ALL but with no significant difference between ANLL and ALL.Conclusion: Probably as one of important mechanisms of acute leukemic immune evasion,IL-10 secreted by leukemic cells,contributing to the immunosuppressive state at the tumor site,increase significantly in acute leukemic patients.
文摘Objective: To explore the expressions of IL-10 on leukemic cells in acute leukemia patients and its significance. Methods: The expressions of IL-10 on leukemic cells in thirty patients was measured by indirect immunofluorescence technique. Results: Observed yellow-green bright fluorescence on leukemic cells membrane, the positive rate of cells was 10-80%, there were 18 patients expressing IL-10 (18/30, 60%) positively, among them 11 with ANLL (11/19, 58%) and 7 with ALL (7/11, 64%) respectively while that of peripheral mononucleate cells in control group was 13%. Compared with that in the control group, there was a significant increase of positive rate in ANLL and ALL but with no significant difference between ANLL and ALL. Conclusion: IL-10 secreted by leukemic cells, contributed to the immunosuppressive state at the tumor site. This is probably one of the important mechanisms of acute leukemic escape.
文摘BACKGROUND Accumulating evidence demonstrates that autoimmune hematopoietic failure and myeloid neoplasms have an intrinsic relationship with regard to clonal hematopoiesis and disease evolution.In approximately 10%-15%of patients with severe aplastic anemia(SAA),the disease phenotype is transformed into myeloid neoplasms following antithymocyte globulin plus cyclosporine-based immunosuppressive therapy.In some of these patients,myeloid neoplasms appear during or shortly after immunosuppressive therapy.Leukemic transformation in SAA patients during anti-tuberculosis treatment has not been reported.CASE SUMMARY A middle-aged Chinese female had a 6-year history of non-SAA and a 2-year history of paroxysmal nocturnal hemoglobinuria(PNH).With aggravation of systemic inflammatory symptoms,severe pancytopenia developed,and her hemoglobinuria disappeared.Laboratory findings in cytological,immunological and cytogenetic analyses of bone marrow samples met the diagnostic criteria for“SAA.”Definitive diagnosis of disseminated tuberculosis was made in the search for infectious niches.Remarkable improvement in hematological parameters was achieved within 1 mo of anti-tuberculosis treatment,and complete hematological remission was achieved within 4 mo of treatment.Frustratingly,the hematological response lasted for only 3 mo,and pancytopenia reemerged.At this time,cytological findings(increased bone marrow cellularity and an increased percentage of myeloblasts that accounted for 16.0%of all nucleated hematopoietic cells),immunological findings(increased percentage of cluster of differentiation 34+cells that accounted for 12.28%of all nucleated hematopoietic cells)and molecular biological findings(identification of somatic mutations in nucleophosmin-1 and casitas B-lineage lymphoma genes)revealed that“SAA”had transformed into acute myeloid leukemia with mutated nucleophosmin-1.The transformation process suggested that the leukemic clones were preexistent but were suppressed in the PNH and SAA stages,as development of symptomatic myeloid neoplasm through acquisition and accumulation of novel oncogenic mutations is unlikely in an interval of only 7 mo.Aggravation of inflammatory stressors due to disseminated tuberculosis likely contributed to the repression of normal and leukemic hematopoiesis,and the relief of inflammatory stressors due to anti-tuberculosis treatment contributed to penetration of neoplastic hematopoiesis.The concealed leukemic clones in the SAA and PNH stages raise the possibility of an inflammatory stress-fueled antileukemic mechanism.CONCLUSION Aggravated inflammatory stressors can repress normal and leukemic hematopoiesis,and relieved inflammatory stressors can facilitate penetration of neoplastic hematopoiesis.
文摘Sunitinib is an orally administered, multi-target tyrosine kinase inhibitor that has been approved by the FDA for the treatment of renal cell carcinoma and imatinib resistant gastro-intestinal tumors. Anti-leukemic activity of sunitinib has been examined in early clinical trials with limited success. However, recent trials on acute myeloid leukemia (AML) patients carrying FLT3 mutations have shown promising results. Effects of sunitinib on leukemic clonogenic cells and potential leukemic stem cells have not been examined so far. We analyzed the anti-proliferative and apoptotic properties of sunitinib on AML-derived cell lines. We also tested the effect of sunitinib on AML patient derived clonogenic cells (AML-CFC), as well as flow-sorted potential leukemic progenitors. Peripheral blood or bone marrow samples were obtained from newly diagnosed AML patients and flow sorted for CD34+ CD133+ or ALDH+ cells. Umbilical cord blood derived CD34+ cells were used as normal controls. Sunitinib induced growth arrest and apoptosis in AML derived cell lines. In addition, 7 μM sunitinib induced 75% reduction of AML-CFC as compared to DMSO treated control (±6.79%;n = 4). In contrast, 7 μM sunitinib treatment of umbilical cord blood derived normal CD34+ cells showed 29% reduction in AML-CFC (±6.77%;n = 5). Treatment of ALDH+ cells sorted from 2 AML cases and CD34+ CD133+ cells from one patient showed reduction of AML-CFC on treatment with sunitinib. Our study highlighted a potent anti-proliferative and proapoptotic effect of sunitinib on AML cell lines, AML patient derived clonogenic cells and potential leukemic stem cells.
文摘This report characterizes the J6-1 cell line derived from a Chinese acute myelomonocytic leukemia patient and previously reported to be associated with EBV. These studies showed that J6-1 cells were also infected with HHV-6 as demonstrate at the DNA level by PCR and Southern blot hybridization and by expression of HHV-6 early membrane antigen on the J6-1 cell surface. Further characterization showed J6-1 was co-infected with EBV type 2. Generally, cells infected with EBV type 2 do not grow well in vitro. However, J6-1 , although difficult to maintain in vitro, has been grown for 15 years. Possibly, co-infection with HHV6 confers this property. In this regard, J6-1 cells exhibited density dependent growth which could be inhibited with an anti-HHV-6-MA monoclonal antibody(MAb). In contrast, anti-HHV-6-VCA MAb stimulated the J6-1 cell proliferation. Electron microscopic analysis showed that, morphologically, there were two types of J6-1 cell, one with lymphoblastoid features and one with a monocytoid appearance. Accordingly, the flow profile of the J6-1 cell line showed heterogeneity. with two populations comprised of CD15-, CD19+ cells with low light scatter(small cells) and a population with greater light scatter(larger cells) which was CD15+ , CD19+. The population was negative for progenitor cell markers(CD33, 34 ), and T cell markers. Southern analysis showed no T cell receptor rearrangement, however there was a clonal JH and kappa light chain expressing population. Glycocytochemical analysis showed several endogenous lectin receptors on the J6-1 cell surface: BSA-Xylose, BSA-Rhamnose, BSAGal. BSA-Lac. This cell line shares many characteristics with other monocytic/ lymphoblastoid cell lines isolated elsewhere and provides circumstantial evidence linking Herpes viruses, as least as co- factors,to leukemia cell growth.
基金Science and Technology of Guangzhou City (2001-Z-037-01)Guangdong Province (99M1204G)
文摘Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymerase chain reaction enzyme-linked immunoassay (PCR-ELISA) in K562 cellstreated with ASODN and hTERT mRNA expression was detected by reverse transcriptase polymerase chain reaction (RT-PCR).Results The hTERT mRNA level was decreased, and teloraerase activity was significantly inhibited when the K562 cells were treated withASODN for 48 h.Conclusion It is suggested that hTERT ASODN might specifically inhibit telomerase activity of K562 cells at translation level, and it isfurther proved that hTERT gene has significant correlation with telomerase activity.
基金This project wassupport by a grantfrom National NaturalSciences Foundation ofChina(No. 39770 934)
文摘To investigate whether the Bcl- 2 gene family is involved in m odulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL - 6 0 cell line and primary acute m yelogenous leukem ic cells,the Bcl- 2 family member Mcl- 1,Bax and Bak and cell cycle proteins including P2 7kipl,P2 1wafl,cyclin D3and p Rbp- were selected and their ex- pression detected by SABC imm uno- histochem ical stain m ethod.The attitude of sub- G1 peak in DNA histogram was determined by FCM.The TU NEL positive cell percentage was identified by term inal deoxynucleotidyl transferase (Td T ) - m ediated Biotin d U NP end labeling technique.It was found that when HL - 6 0 cells were treated with 2 5μm ol/ L curcumin for 2 4 h,the expression level of Mcl- 1was down- regulated,but that of Bax and Bak up- regulated time- dependently.There was significant difference in the expression level of Mcl- 1,Bax and Bak between the curcumin- treated groups and control group(P<0 .0 5 - 0 .0 1) .At the sam e time,curcumin had no effect on progress of cell cycle in prim aty acute m yelogenous leukemia at newly diagnosis,but could in- crease the peak of Sub- G1 (P<0 .0 5 ) ,and down- regulate the expression of Mcl- 1and up- regulate the expression of Bax and Bak with the difference being statistically significant.The expression of P2 7kipl,P2 1wafl and p Rbp- were elevated and thatof cyclin D3decreased in the presence of curcum in. These findings suggested thatthe Bcl- 2 gene fam ily indeed participated in the regulatory process of apoptosis induced by curcumin in HL - 6 0 cells and AML cells.Curcumin can induce apoptosis of primary acute myelogenous leukemic cells and disturb cell cycle progression of HL - 6 0 cells.The m echanism appeared to be m ediated by perturbing G0 / G1 phases checkpoints which associated with up- regulation of P2 7kipl,P2 1wafl and p Rbp- expression,and down- regulation of cyclin D3.
基金Thisprojectwassupported by a grant from the NationalNaturalScienceFoundationofChina(No.39970322)andTrans-CenturyTrainingProgramFoundation for Talent un-der the supervision of the Ministry of Education of China
文摘To investigate the inducement of cytotoxic T lym phocytes(CTL s) by antigen peptides m ixture from different leukemia cells and the cross- reaction of the m ixtures from different cell lines,antigen peptides m ixtures were prepared from different leukemia cell lines respectively and then bound with Hsp70 in vitro.Activation and proliferation of PBMC were observed after stim u- lation with different Hsp70 - peptide complexes.The ratio of CD8+ in proliferative cells was ana- lyzed by flow cytometry.The cytotoxicity of the activated PBMC to different target cells was as- sayed.The results showed that the antigen peptides from different leukemia cell lines,bound with Hsp70 ,could activate PBMC effectively,and stimulate the activated PBMC to proliferate.The proliferative PBMC had specific cytotoxicity to corresponding leukem ia cells.CD8+ cells,account- ing for a high proportion in proliferative cells,had a specific cytotoxicity to leukemia cells from which antigen peptides were prepared,suggesting that these CD8+ cells were CTL s specific to leukemia cells.CTL s activated by Hut78- peptides or Molt4 - peptides had a significantly stronger cytotoxicity to Hut78cells,Molt4 cells and Jurkat cells than that of CTL s activated by HL - 6 0 - peptides(P<0 .0 5 ) .And the cytotoxicity of CTL s activated by Hut78/ Molt4 - peptides to Jurkat cells was significantly stronger than that of CTL s activated by either Hut78- peptides or Molt4 - peptides alone(P<0 .0 5 ) .It is concluded that antigen peptides m ixtures from leukem ia cells can induce specific antitumor CTL s.There exists cross- reactivity among antigen peptides m ixtures from different cell lines of the sam e type leukemia and more cross- reactive antigen peptides could be obtained from m ore cell lines,suggesting that antigen peptides m ixture with broad antigenic spectrum could be prepared by using multiple leukemia cell lines.
基金This work was supported by the National Natural Science Foundation of China (No. 39770330).
文摘Objective: To study the molecular mechanism ofdifferent tumorigenicity in nude mice of human leukemiacell lines K562-n and K562. Methods: To analyze the genes differently expressed between K562 and K562-n cells byusing cDNA microarray technique. Results: Among the12800 genes detected, some genes involved in materialmetabolism and material transport were differentlyexpressed between K562-n and K562 cells. These genesinclude homo sapiens placenta-specific ATP-binding cassette transporter gene, dihydrodiol dehydrogenase gene, hepatic dihydrodiol dehydrogenase gene, NAD-dependent methylene tetrahydrofolate dehydrogenase cyclohydrolase,lysophosphatidic acid acyltransferase, alpha gene,argininosuccinate lyase gene, mitochondrial isocitrtatedehydrogenase, adhesion protein SQM1 gene, dimethylarginine dimethylamino-hydrolase gene, M1subunit of ribonucleotide reductase and farnesylpyrophosphate synthetase gene. Conclusion: The hightumorigenicity of K562-n cells is related to the differentexpression of some genes concerned with cell metabolismand material transpoert.
文摘The effect of 1,25-dihydroxyvitamin D<sub>3</sub> [1,25（OH）<sub>2</sub>D<sub>3</sub>] and13-cis-retinoic acid（RA）on the proliferation of a novel human megakaryoblasticleukemia cell line（HIMeg）was investigated.At the concentration of 10<sup>9</sup> 10<sup>6</sup>mol/L,1,25（OH）<sub>2</sub>D<sub>3</sub> and RA showed significant inhibition of the proliferation of themegakaryoblastic leukemic cells,which was demonstrated by the count of survival cells,incorporation of<sup>3</sup>H-TdR and<sup>3</sup>H-UR,and cloning efficiency in dose-dependent and time-dependent manners.The results can further explain the mechanism of differentiation-inducing agents and the effect of 1 ,25（OH）<sub>2</sub>D<sub>3</sub> on myelofibrosis.It is possible for1,25（OH）<sub>2</sub>D<sub>3</sub> and RA to be used to treat malignant megakaryocytic diseases.
文摘Objective: To establish a HPLC method using fluorometric detection for quantitatively determinating intracellular accumulation of verapamil (VER). Methods: Chromatography column was packed with spherisorb ODS(250×4.6 mm,10 μm).The mobile phase consisted of the mixture of methanol:NaAC (0.01 mol/L): diethylamine (65:35:0.25). The detect wavelength was 280/310 nm (Ex/Em). Results: The standard curve showed a good correlation between concentration and peak area within the range of 5-50 ng/ml. RSD was 0.86%, and recovery radio of loading sample, 100%. The detection limit for cell sample was 0.2-148 ng/ml. Intracellular accumulation of VER was observed to decrease from a 13 fold to 5 fold in K562/ADM cells, and from a 3.5 fold to 4.3 fold in K562/VER cells and from a 2.1 fold to 6.5 fold in K562/ADM/VER cells, compared with the relevant control cells. Conclusion: HPLC method was proved to be sensitive and specific for using to quantitatively determine the intracellular accumulation of VER.
基金the grantof National NatureScience Foundation of China(Serial No. 3 9770 767)
文摘To assess the value of CD34 + cells transferred exogenous Fas ligand (FasL) in inducing apoptosis of human leukemic cells, the CD34 + cells transfected with F asL or without, pretreated with mitomycin C, was mixed with leukemic cell line U937 cells in presence or absence of daunorubicin (DNR) or cytosine arabinoside (Ara C). After l8 h, apoptosis of cells was detected by FCM and TUNEL. Induced for l8 h by CD34 + cells transfected with FasL or without, the ratio of apoptos is of U937 cells was (5.0±1.3) %, (10.8±0.6) % ( P < 0.01), respectively. Induced by FasL +CD34 ++DNR, FasL +CD34 ++Ara C, the ratio was (13.4±1.0) % ( P < 0.05), (17.9±1.3)% ( P <0.01), respectively. The result demonstrated that CD34 + cells transfected with exogenous FasL could induce apoptosis of human leukemic cells and showed a cytotoxic synergistic effect when used in combination with chemotherapeutic drugs, suggesting that it was possible to develop a new method in treatment of leukemia.
文摘Leukemia is a most prevalent type of cancer around the globe. Due to major side effects of Chemotherapy and radiotherapy, scientists worked to explore the alternative source to treat leukemia. An alternative source for the treatment of leukemia existed in the form of curcumin, a natural phenolic compound extracted from curcuma longa plant. It exhibited anticancer properties reducing the tumor load via apoptosis and cell cycle arrested in various cancer cell lines and controlled tumor proliferation by blocking tumor inducing gene such as FLT3, Akt gene, ROS and NF-κB inhibition. At molecular level, curcumin plays a key therapeutic role in protection of normal cells by up regulation of NRF-2 that induces production of cellular antioxidants. It regulates various signaling pathways including NF-KB, JAK/STAT, PI3K/AKT and JNK pathways, thereby affecting cancer initiation, progression, and metastasis. This review described the potential of curcumin for treatment of leukemia;it affects different signaling cascades and their regulation. This study provides a preclinical foundation for future usage of curcumin in the treatment of cancer.
